This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. ABSTRACT: Type 1 diabetes mellitus (T1DM) is currently managed using modulation of dietary carbohydrates and insulin. Paradoxical post-meal hyperglucagonemia is associated with post-prandial hyperglycemia in T1DM. Glucagon suppressors such as the amylin analog, pramlintide, and the glucagon like peptide-1 (GLP-1) analog, exenatide, are new agents approved for use in adults with diabetes. We have previously demonstrated pramlintide reduces post-prandial hyperglycemia by decreasing glucagon and delaying gastric emptying in adolescents with T1DM. GLP-1 in animal studies has been shown to increase beta cell mass and decrease apoptosis. Only limited information is available on the use of GLP-1 in T1DM. No studies have been reported to determine if pramlintide and exenatide have similar effects on glycemic control in T1DM. The overall aim of this proposal is to develop safe and effective strategies targeting glucagon and improving glycemic control in pediatric T1DM. In current protocol, we hypothesize that exenatide/pramlintide will be better than insulin alone in improving glycemic control in longstanding T1DM. Secondarily comparisons between pramlintide and exenatide will be undertaken. Uses of exenatide and/or pramlintide provide us with potentially new tools to improve glycemic control in children and adolescents with T1 DM and thus reduce associated long-term microvascular complications of this debilitating disease. I. HYPOTHESIS: Postprandial glucose excursions improve with adjunctive therapy of exenatide or pramlintide with insulin as compared to mono-therapy of insulin. II. SPECIFIC AIMS: 1) To examine the effect of exenatide vs pramlintide adjunctive therapy in addition to insulin on glycemic control in T1DM as compared to mono-therapy of insulin. 2) To compare the efficacy of pramlintide vs exenatide when combined with insulin on glycemic control in T1DM.